GERENCIA DE ÁREA INVESTIGACIÓN, DESARROLLO E INNOVACIÓN (GAIDI)
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Examinando GERENCIA DE ÁREA INVESTIGACIÓN, DESARROLLO E INNOVACIÓN (GAIDI) por Autor "Abramson, Guillermo"
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Ítem Acceso Abierto A spatially extended model to assess the role of landscape structure on the pollination service of Apis mellifera(Board, 2020) Joseph, Julien; Santibáñez, Fernanda; Laguna, María Fabiana; Abramson, Guillermo; Kuperman, Marcelo Néstor; Garibaldi, Lucas AlejandroApis mellifera plays a crucial role as pollinator of the majority of crops linked to food production and thus its presence is currently fundamental to our health and survival. The composition and configuration of the landscape in which Apis mellifera lives will likely determine the well-being of the hives and the pollination service that their members can provide to the crops. Here we present a spatially explicit model that predicts the spatial distribution of visits by Apis mellifera to crops, by simulating daily trips of honey bees, the demographical dynamic of each hive and their honey production. This model goes beyond existing approaches by including 1) a flower resource affected by the feedback interaction between nectar extraction, pollination, blossoming and repeated visits, 2) a pollinators dynamic that allows competition through short term resource depletion, 3) a probabilistic approach of the foraging behavior, modeling the fact that the pollinators have only partial knowledge of the resource on their surroundings, and 4) the specific and systematic foraging behavior and strategies of Apis mellifera at the moment of choosing foraging sites, as opposed to those adopted by solitary and wild pollinators. With a balance between simplicity and realism we show the importance of keeping a minimal fraction of natural habitat in an agricultural landscape. We also evaluate the effects of the landscape’s structure on pollination, and demonstrate that there exists an optimal size of natural habitat patches that maximizes the pollination service for a fixed fraction of natural habitat.Ítem Acceso Abierto Digging the topology of rock art in northwestern Patagonia(Oxford University Press, 2020) Vargas, Fernando E.; Lanata, José L.; Abramson, Guillermo; Kuperman, Marcelo Nesto; Fiore, DáneaWe present a study on the rock art of northern Patagonia based on network analysis and communities detection. We unveil a significant aggregation of archaeological sites, linked by common rock art motifs that turn out to be consistent with their geographical distribution and archaeological background of hunter-gatherer stages of regional peopling and land use. This exploratory study will allow us to approach more accurately some social strategies of visual communication entailed by rock art motif distribution, in space and time.Ítem Acceso Abierto Mathematical model of livestock and wildlife: Predation and competition under environmental disturbances(Elsevier Science, 2015-08-10) Laguna, Maria Fabiana; Abramson, Guillermo; Kuperman, Marcelo Nestor; Lanata, Jose Luis; Monjeau, Jorge AdrianInspired by real scenarios in Northern Patagonia, we analyze a mathematical model of a simple trophic web with two herbivores and one predator. The studied situations represent a common practice in the steppes of Argentine Patagonia, where livestock are raised in a semi-wild state, either on the open range or enclosed, coexisting with competitors and predators. In the present work, the competing herbivores represent sheep and guanacos, while the predator is associated with the puma. The proposed model combines the concepts of metapopulations and patches dynamics, and includes an explicit hierarchical competition between species, which affects their prospect to colonize an empty patch when having to compete with other species. We perform numerical simulations of spatially extended metapopulations assemblages of the system, which allow us to incorporate the effects of habitat heterogeneity and destruction. The numerical results are compared with those obtained from mean field calculations. We find that the model provides a good theoretical framework in several situations, including the control of the wild populations that the ranchers exert to different extent. Furthermore, the present formulation incorporates new terms in previously analyzed models that help to reveal the important effects due to the heterogeneous nature of the system.Ítem Acceso Abierto Peculiar: Centaurus A(Planetario de la Ciudad de Buenos Aires Galileo Galilei, 2014-03) Abramson, GuillermoHe aquí Centaurus A, también conocida como NGC 5128. Es una de las galaxias más brillantes, una de las joyitas del cielo austral. Los astrónomos clasifican a esta galaxia como “peculiar”. Aún para un ocasional astrónomo aficionado, una foto como ésta no deja lugar a dudas: es peculiarÍtem Acceso Abierto Random-walk model to study cycles emerging from the exploration-exploitation trade-off(American Physical Society, 2015-01-13) Kazimierski, Laila Daniela; Abramson, Guillermo; Kuperman, Marcelo NestorWe present a model for a random walk with memory, phenomenologically inspired in a biological system. The walker has the capacity to remember the time of the last visit to each site and the step taken from there. This memory affects the behavior of the walker each time it reaches an already visited site modulating the probability of repeating previous moves. This probability increases with the time elapsed from the last visit. A biological analog of the walker is a frugivore, with the lattice sites representing plants. The memory effect can be associated with the time needed by plants to recover its fruit load. We propose two different strategies, conservative and explorative, as well as intermediate cases, leading to nonintuitive interesting results, such as the emergence of cycles.Ítem Acceso Abierto ¿Sustentabilidad?(Red latinoamericana y del Caribe de bioética-UNESCO, 2015-01-01) Monjeau, Jorge Adrian; Lanata, Jose Luis; Kuperman, Marcelo Nestor; Abramson, Guillermo; Laguna, Maria FabianaAbordamos el problema de la sustentabilidad desde la teoría de la construcción de nicho sumando a ésta un enfoque biofísico y energético. Presentamos el desarrollo teórico de un modelo matemático que acopla el crecimiento poblacional con el hábito en el uso de los recursos. En el modelo, cada individuo representa un factor de conversión y disipación de materia y energía de la biósfera en biomasa de Homo sapiens y en cultura material, estableciendo una vinculación matemática entre demografía, consumo, y deterioro de los recursos, escenario a ser heredado por las generaciones futuras. Ejemplificamos distintos escenarios de población y consumo y alternativas matemáticas para resolver la sustentabilidad. Una nueva sociedad futura justa, que satisfaga las necesidades de calidad de vida de todos los individuos presentes y futuros evitando la destrucción de especies y ecosistemas será aquella que pueda subordinar las leyes humanas a las leyes naturales, cualquier otro modo es inviable.Ítem Acceso Abierto Tell me where you live and I'll tell you who you are: Spatial segregation of southern species of Eligmodontia Cuvier in Patagonia, Argentina(Elsevier, 2020) Ruiz Barlett, Trinidad; Martin, Gabriel; Laguna, María Fabiana; Abramson, Guillermo; Monjeau, AdrianEligmodontia morgani y E. typus son dos pequeños (<25 g) roedores sigmodontinos que habitan los ambientes áridos del sur de Argentina. Debido a que las especies son difíciles de distinguir en el campo, su delimitiación geográfica siempre ha sido controvertida. En este trabajo usamos registros donde las especies fueron identificadas por su cariotipo y ADN mitocondrial, y modelamos su distribución potencial usando análisis de máxima entropía. Nuestros resultados muestran una segregación en el nicho entre las especies, mayormente impulsado por la temperatura. Los modelos ecológicos de nicho muestran que E. morgani es un habitante del oeste y centro patagónico correspondientes con la ecorregión de la Estepa Patagónica, mientras E. typus es un habitante de las regiones centrales y el este patagónico, correspondientes con la ecorregión del Monte. En áreas de ecotono, nuestros modelos predicen que E. morgani ocupa las zonas altas y frías de las mesetas, mientras que E. typus ocupa zonas bajas con una matriz de vegetación de la Ecorregión del Monte. Nuestros modelos matemáticos muestran una selección de hábitat de temperaturas medias mínimas de 1 °C y 5 °C para E. morgani y E. typus, respectivamente, y de temperaturas máximas medias de 22 °C y de 27 °C para cada especie.